juice added to the gym

.travis.yml

@@ -22,14 +22,6 @@ matrix:
     sudo: required
     services:
     - docker
-  - env: PYKEP_BUILD="manylinux64Py27" DOCKER_IMAGE="pagmo2/manylinux1_x86_64_with_deps"
-    sudo: required
-    services:
-    - docker
-  #- env: PYKEP_BUILD="manylinux64Py27mu" DOCKER_IMAGE="pagmo2/manylinux1_x86_64_with_deps"
-  #  sudo: required
-  #  services:
-  #  - docker
 install:
 - docker pull $DOCKER_IMAGE
 script:

appveyor.yml

@@ -11,7 +11,7 @@ environment:
     #- BUILD_TYPE: "Release"
     - BUILD_TYPE: "Python36-x64"
     - BUILD_TYPE: "Python37-x64"
-    - BUILD_TYPE: "Python27-x64"
+
 
 install:
 - if [%BUILD_TYPE%]==[MSVC_64_Python36] set PATH=C:\Miniconda36-x64\Scripts;%PATH%

pykep/test.py

@@ -168,7 +168,20 @@ def run_tandem_test(self):
         4.21911761e-01,  3.38579352e+02, -1.68143357e+00,  1.10121434e+00,
         6.39679220e-01,  1.17925136e+03, -2.02838607e+00,  1.05000000e+00,
         2.31554532e-01,  1.80000707e+03]
-        self.assertAlmostEqual(udp.fitness(x)[0], -7.355990585895818)
+        self.assertAlmostEqual(udp.fitness(x)[0], -7.302117213470749)
+
+    def run_juice_test(self):
+        from .trajopt import gym
+        udp = gym.tandem(prob_id = 6, constrained=False)
+        x = [ 8.16283083e+03,  6.41922787e-01,  6.51202691e-01,  2.51009414e+03,
+        2.97841478e-01,  3.81541370e+02,  9.58572190e-01,  1.53007674e+00,
+        3.06125365e-01,  1.49264351e+02,  4.10103546e+00,  2.39297670e+00,
+        4.34424957e-01,  3.16066418e+02,  4.33225338e+00,  1.30946367e+00,
+        4.52048883e-01,  1.63208108e+02,  5.93850330e-01,  1.34871269e+00,
+        2.03288502e-01,  6.52494606e+02, -1.37902374e+00,  1.55482534e+00,
+        1.96917559e-01,  1.08471126e+03]
+        self.assertAlmostEqual(udp.fitness(x)[0], -7.987614956531155)
+
 
 
 def run_test_suite(level=0):

pykep/trajopt/_juice.py

@@ -34,3 +34,67 @@ def __init__(self):
             eta_ub=0.99,
             rp_ub=10
         )
+
+    def fitness(self, x):
+        T, Vinfx, Vinfy, Vinfz = self._decode_times_and_vinf(x)
+        # We transform it (only the needed component) to an equatorial system rotating along x 
+        # (this is an approximation, assuming vernal equinox is roughly x and the ecliptic plane is roughly xy)
+        earth_axis_inclination = 0.409072975
+        # This is different from the GTOP tanmEM problem, I think it was bugged there as the rotation was in the wrong direction.
+        Vinfz = - Vinfy * sin(earth_axis_inclination) + Vinfz * cos(earth_axis_inclination)
+        # And we find the vinf declination (in degrees)
+        sindelta = Vinfz / x[3]
+        declination = asin(sindelta) / np.pi * 180.
+        # We now have the initial mass of the spacecraft
+        m_initial = launchers.ariane5(x[3] / 1000., declination)
+        # And we can evaluate the final mass via Tsiolkowsky
+        Isp = 312.
+        g0 = 9.80665
+        DV = super(_juice_udp, self).fitness(x)[0]
+        DV = DV + 275.  # losses for 5 swingbys + insertion
+        m_final = m_initial * exp(-DV / Isp / g0)
+        # Numerical guard for the exponential
+        if m_final == 0:
+            m_final = 1e-320
+        return [-log(m_final), ]
+
+    def get_name(self):
+        return "JUICE"
+
+    def get_extra_info(self):
+        retval = "\t Sequence: " + \
+            [pl.name for pl in self._seq].__repr__()
+        return retval
+
+    def pretty(self, x):
+        """
+        prob.plot(x)
+
+        - x: encoded trajectory
+
+        Prints human readable information on the trajectory represented by the decision vector x
+
+        Example::
+
+          print(prob.pretty(x))
+        """
+        super(_juice_udp, self).pretty(x)
+        T, Vinfx, Vinfy, Vinfz = self._decode_times_and_vinf(x)
+        # We transform it (only the needed component) to an equatorial system rotating along x 
+        # (this is an approximation, assuming vernal equinox is roughly x and the ecliptic plane is roughly xy)
+        earth_axis_inclination = 0.409072975
+        # This is different from the GTOP tanmEM problem, I think it was bugged there as the rotation was in the wrong direction.
+        Vinfz = - Vinfy * sin(earth_axis_inclination) + Vinfz * cos(earth_axis_inclination)
+        # And we find the vinf declination (in degrees)
+        sindelta = Vinfz / x[3]
+        declination = asin(sindelta) / np.pi * 180.
+        m_initial = launchers.ariane5(x[3] / 1000., declination)
+        # And we can evaluate the final mass via Tsiolkowsky
+        Isp = 312.
+        g0 = 9.80665
+        DV = super(_juice_udp, self).fitness(x)[0]
+        DV = DV + 275.  # losses for 5 swgbys + insertion
+        m_final = m_initial * exp(-DV / Isp / g0)
+        print("\nInitial mass:", m_initial)
+        print("Final mass:", m_final)
+        print("Declination:", declination)

pykep/trajopt/_launchers.py

@@ -40,6 +40,37 @@
     [1e-3, 1e-3, 1e-3, 1e-3, 1e-3, 1e-3]
 ]
 
+# Ariane 5: data provided to ESOC by Arianespace when they were still considering Ariane launch for ExoMars. 
+# Negative mass values have been substituted with exp(m/1000) to avoid problems.
+# Declination has been extended up to 90 degrees.
+_vinfs_Ariane5 = [0.5, 1. , 1.5, 2. , 2.5, 3. , 3.5, 4. , 4.5, 5. , 5.5, 6. ]
+_decls_Ariane5 = [-90, -50, -45, -40, -35, -30, -25, -20, -15, -10, -5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 90]
+_data_Ariane5 = [
+    [4.97870684e-02, 3.01973834e-02, 1.83156389e-02, 1.11089965e-02, 6.73794700e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04, 1.23409804e-04, 4.53999298e-05, 1.67017008e-05, 6.14421235e-06],
+    [4.97870684e-02, 3.01973834e-02, 1.83156389e-02, 1.11089965e-02, 6.73794700e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04, 1.23409804e-04, 4.53999298e-05, 1.67017008e-05, 6.14421235e-06],
+    [8.20849986e-02, 4.97870684e-02, 3.01973834e-02, 1.83156389e-02, 1.11089965e-02, 6.73794700e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04, 1.23409804e-04, 4.53999298e-05, 1.67017008e-05],
+    [1.35335283e-01, 8.20849986e-02, 4.97870684e-02, 2.55785799e-02, 1.83156389e-02, 1.11089965e-02, 6.73794700e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04, 1.23409804e-04, 4.53999298e-05],
+    [2.23130160e-01, 1.35335283e-01, 1.35335283e-01, 8.20849986e-02, 4.97870684e-02, 1.83156389e-02, 1.11089965e-02, 4.08677144e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04, 1.23409804e-04],
+    [3.67879441e-01, 2.63685018e-01, 2.23130160e-01, 1.89001562e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 6.73794700e-03, 4.08677144e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04],
+    [6.06530660e-01, 5.13759511e-01, 3.67879441e-01, 2.63685018e-01, 1.89001562e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 6.73794700e-03, 4.08677144e-03, 2.47875218e-03, 9.11881966e-04],
+    [5.00600000e+03, 4.66700000e+03, 6.06530660e-01, 3.67879441e-01, 2.63685018e-01, 1.89001562e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 1.11089965e-02, 6.73794700e-03, 2.47875218e-03],
+    [5.47400000e+03, 5.19500000e+03, 4.80500000e+03, 4.31600000e+03, 7.16770194e-01, 5.13759511e-01, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 1.11089965e-02, 6.73794700e-03],
+    [5.83500000e+03, 5.61500000e+03, 5.29100000e+03, 4.87000000e+03, 4.35900000e+03, 3.77400000e+03, 3.13600000e+03, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 1.83156389e-02],
+    [6.07800000e+03, 5.91000000e+03, 5.64800000e+03, 5.29500000e+03, 4.85600000e+03, 4.34000000e+03, 3.76300000e+03, 3.14100000e+03, 3.67879441e-01, 2.23130160e-01, 1.35335283e-01, 4.97870684e-02],
+    [6.19100000e+03, 6.05900000e+03, 5.84400000e+03, 5.54900000e+03, 5.18000000e+03, 4.74400000e+03, 4.25100000e+03, 3.71400000e+03, 3.15500000e+03, 6.06530660e-01, 3.67879441e-01, 1.35335283e-01],
+    [6.07300000e+03, 5.95300000e+03, 5.74900000e+03, 5.47000000e+03, 5.12700000e+03, 4.72900000e+03, 4.28600000e+03, 3.80800000e+03, 3.30400000e+03, 2.78500000e+03, 2.26000000e+03, 3.67879441e-01],
+    [3.67879441e-01, 3.32871084e-01, 3.01194212e-01, 2.72531793e-01, 2.46596964e-01, 2.23130160e-01, 2.01896518e-01, 1.82683524e-01, 1.65298888e-01, 1.49568619e-01, 1.35335283e-01, 1.22456428e-01],
+    [1.35335283e-01, 1.22456428e-01, 1.10803158e-01, 1.00258844e-01, 9.07179533e-02, 8.20849986e-02, 7.42735782e-02, 6.72055127e-02, 6.08100626e-02, 5.50232201e-02, 4.97870684e-02, 4.50492024e-02],
+    [2.23130160e-01, 2.63685018e-01, 3.67879441e-01, 4.72366553e-01, 6.06530660e-01, 7.78800783e-01, 4.08100000e+03, 3.50900000e+03, 2.89100000e+03, 2.24400000e+03, 3.67879441e-01, 1.35335283e-01],
+    [3.67879441e-01, 4.72366553e-01, 6.06530660e-01, 7.78800783e-01, 4.87400000e+03, 4.39100000e+03, 3.83600000e+03, 3.22000000e+03, 2.55900000e+03, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02],
+    [6.06530660e-01, 7.78800783e-01, 5.48400000e+03, 5.13400000e+03, 4.69300000e+03, 4.16700000e+03, 3.56300000e+03, 2.89700000e+03, 2.19000000e+03, 2.23130160e-01, 4.97870684e-02, 1.83156389e-02],
+    [5.77300000e+03, 5.58900000e+03, 5.30600000e+03, 4.92400000e+03, 4.44300000e+03, 3.86800000e+03, 3.21000000e+03, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 6.73794700e-03],
+    [5.65000000e+03, 5.44100000e+03, 5.12400000e+03, 4.69700000e+03, 4.16100000e+03, 3.52200000e+03, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 6.73794700e-03, 2.47875218e-03],
+    [5.47700000e+03, 5.23900000e+03, 4.88200000e+03, 4.40100000e+03, 3.79500000e+03, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 6.73794700e-03, 2.47875218e-03, 9.11881966e-04],
+    [5.30200000e+03, 5.02100000e+03, 4.60400000e+03, 4.04400000e+03, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 6.73794700e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04],
+    [5.30200000e+03, 5.02100000e+03, 4.60400000e+03, 4.04400000e+03, 3.67879441e-01, 1.35335283e-01, 4.97870684e-02, 1.83156389e-02, 6.73794700e-03, 2.47875218e-03, 9.11881966e-04, 3.35462628e-04]
+]
+
 class _launchers:
     """
     This class contains a few functions that return the mass launchers can deliver
@@ -59,6 +90,7 @@ class _launchers:
     def __init__(self):
         self._atlas501 = interp2d(_vinfs_A5, _decls_A5, _data_A5, kind='linear', fill_value=0.1, copy=False)
         self._soyuzf = interp2d(_vinfs_SF, _decls_SF, _data_SF, kind='linear', fill_value=1e-3, copy=False)
+        self._ariane5 = interp2d(_vinfs_Ariane5, _decls_Ariane5, _data_Ariane5, kind='linear', fill_value=1e-3, copy=False)
     def atlas501(self, vinfs, decls):
         """atlas501(vinfs, decls)
 
@@ -88,3 +120,18 @@ def soyuzf(self, vinfs, decls):
             Numpy array containg the mass delivered to escape with said declinations and magnitudes.
         """
         return self._soyuzf(vinfs, decls)
+    def ariane5(self, vinfs, decls):
+        """ariane5(vinfs, decls)
+
+        Computes the mass that the Ariane5 launcher can deliver to a certain vinf and declination, assuming
+        a launch from Kourou. Data provided to ESOC by Arianespace when Ariane launch for ExoMars was an option.
+        If the inputs are arrays, then a mesh is considered and the mass is returned on points of the mesh.
+
+        Args:
+            - vinfs (``float`` or array-like): the hyperbolic escape velocity in km/s
+            - decls (``float`` or array-like): the declination in degrees
+
+        Returns:
+            Numpy array containg the mass delivered to escape with said declinations and magnitudes.
+        """
+        return self._ariane5(vinfs, decls)

pykep/trajopt/_tandem.py

@@ -95,7 +95,7 @@ def fitness(self, x):
         Isp = 312.
         g0 = 9.80665
         DV = super(_tandem_udp, self).fitness(x)[0]
-        DV = DV + 0.165  # losses for 3 swgbys + insertion
+        DV = DV + 165.  # losses for 3 swgbys + insertion
         m_final = m_initial * exp(-DV / Isp / g0)
         # Numerical guard for the exponential
         if m_final == 0: